Prerequisites

First things first, in order to beat this boss, you need to reach it. This is achieved by winning every single fight in arcade without losing a round in the process. While it sounds harsh at first, there is a catch that makes it way easier to achieve: if you lose a match and hit continue, it doesn’t count the rounds and matches you lost, and you can use as many continues as you want. This means that if you lose a round at any point (including against Nagoriyuki) you can just lose the match on purpose and try again indefinitely. While it doesn’t make the fights easier, it does help by not having to win all this in a row like it was the case in most fighting games before. Once you reach the second and final Nagoriyuki boss fight with him at full power, this is where the challenge really begins.

Basic strategy

Since I used Anji to defeat him, this strategy will heavily  rely on his peculiar abilities, but even you’re using a different character you can still take advantage of the AI behavior I’m going to describe.

When standing next to him or when he gets up:

use Suigetsu no Hakobi, Anji’s dancing move that parries (sort of) attacks if done during the right time frame. Hold the button for a longer animation to make it safer and easier to parry the incoming attack. Nagoriyuki just loves using his slash or heavy slash attack when you’re a bit too close, which we’re using to our advantage here. These moves are slow and perfectly punishable by Anji’s move. After you parry, perform the most efficient combo you can to punish him.

When standing away from him:

When you’re away from him, you need to be on the defensive. Most of his attacks will win yours because in this state he has infinite blood gauge and additional I-frames. He will attack a lot but don’t panic. Just block and wait for an opportinity. The best ones you can get are to either grab him when he teleportsto you, or even better, block his overdrive. This move has an insane recovery, so whenever you block you get to punish and get the upper hand again.

When he’s just standing there:

Sometimes he will space out and not move anymore for a couple seconds. That’s your cue to try and attack him, but he’s usually quick to block anyway, so my advice is to throw him when he’s not moving. It’s usually free.

Getting him into a K.O. state:

While he’s a really tough nut to crack, he’s easily put into a K.O. state when you chain enough attacks in a row together. Taking hits seems to reduce his blood gauge and he faints when it becomes empty, giving you a free combo opportunity.

Managing the wall:

Guilty Gear Strive lets you break the wall with your opponent when you either combo him enough, or hit with an overdrive close to the screen border. This has several benefits depending on how you do it. First of all, breaking the wall means your ressource bar is gonna increase at a faster rate for a few seconds, which is extremely useful. Also, if you break the wall with an overdrive, the opponent will be knocked down on arrival. This is a great advantage, especially for this fight, as you can immediately get back to the strategy of Suigetsu no Hakobi when he gets up.

Air combo:

Alternatively, you could send his flying with a fully charged focus attack when he’s in a K.O. state, getting a full air combo this way. While this is pretty simple and damaging it doesn’t break the wall, so I prefer using overdrives to do so and keep the advantages of both knocking him down and getting more ressources.

The flow I’m after:

The basic strategy is as follow. Right from the beginning of the round, Nagoriyuki will enter blood stance and he’s safe while doing it. If you’re close after he’s done, he will most likely hit you right after, which lets you parry this predictable move and combo him. Once you’re done and he’s knocked down, bait his next attack when he gets up and do it again. If done correctly, this will keep him in a loop of getting baited over and over. Whenever you have enough ressource for an overdrive, finish your combo with it so it will break the wall and knock him down. Then close in and bait him on wake up as usual. Keep this going over and over until he dies. If for some reason he breaks out of this cycle, patiently defend until he gives you the opportunity to start the loop again, such as his failed overdrive.

I hope those tips proved to be helpful! Good luck defeating him!